The mission of Microsoft's Windows 8 operating system is to break down the barrier between the PC and tablet, but it's also a challenge to PC makers to rethink the fundamentals of computer design. Lenovo picked up the gauntlet and ran with it, creating a huge 27-inch monitor that lays flat and becomes an interactive table. The IdeaCentre Horizon has an HD screen, i7 processor, a 2-hour battery, and a specialized multi-user UI called Aura with games and activities oriented towards multiple users. The Horizon should go on sale this summer for around $1600.